This proposal calls for the creation of the Oregon Regional Node (OR- Node) of NIDA's national drug treatment clinical trials network on the basis of an Oregon consortium of the researchers, community treatment programs and the state policy group for substance abuse treatment. This consortium, "Oregon Bridging the Gap Between Practice and Research: Forging Partnerships with Community-Based Drug and Alcohol Treatment (Lamb, Greenlick, and McCarty). The proposed OR-Node is a partnership of three research and training organizations, more than 30 collaborating investigators, and the treatment provider community of the State of Oregon. The research group brings resources from the Oregon Health Sciences University, the Kaiser Permanente Center for Health Research, and the Oregon Research Institute. Investigators and operations personnel from these institutions will form the Regional Research and Training Center (RRTC) of OR-Node. Each of these centers of excellence provides senior research personnel to OR-NODE and each brings a special set of other resources to the partnership, such as the approaches and institutional settings, and provides treatment services to all segments of the Oregon population. The structure of the OR-Node operationalizes a full partnership arrangements among the research institutions and the treatment community. Three research concepts are offered in this proposal, selected to exhibit the full-range of research that can be carried out by the OR-Node researchers and the type of resources OR-Node offers to the national network. The research concepts are: a quantitative and qualitative assessment of the national network treatment programs developing and testing a model of diffusion of innovation among community-based treatment programs, a clinical trial of antidepressants as an adjuvant in behavioral treatment for drug abuse, and a project top enhance the recruitment and treatment of persons with mild or moderate mental retardation with drug abuse or dependency problems.